The European Commission has published three 'Taxation Papers' on corporate taxation. These papers are research items prepared by Commission staff or by experts working in association with them. One paper deals the effective corporate tax rates, another deals with the link between corporate tax and economic distortions, and the third paper deals with multinational firm location decisions.
Tax Paper No 14 "Corporate effective tax rates in an enlarged European Union" is available here. In summary, this paper offers an assessment of European corporate tax regimes using forward-
looking indicators for corporate investment based on a specific methodology. The analysis shows that over time the reduction in the corporate effective average tax rates (EATR) was lower than for the corporate statutory rates and the figures suggest that simple corporate tax base broadening by means of less generous capital allowances is not a sufficient explanation for this phenomenon.
Tax Paper No 15 "Corporate income tax and economic distortions" is available here. In summary, as any non-lump-sum tax, corporate income taxation creates distortions in economic choices, reducing its efficiency.
Tax Paper No 16 "International Taxation and Multinational Firm Location Decisions" is available here. This paper estimates the separate effects of host and parent country taxation on the location decisions of multinational firms.